1. Field of the Invention
The present invention relates to an electric cable guiding device for guiding an electric cable in a U shape in measuring the electric cable and cutting the same to predetermined lengths in the manufacturing processes of a wiring harness.
2. Description of the Related Art
A wiring harness mounted on an automobile or the like is characterized in that it is constructed by assembling a plurality of electric cables cut to predetermined lengths, has flexibility, has a long narrow shape and has a complicatedly branched structure. The manufacturing processes of the wiring harness include the measuring and cutting process for measuring the length of the electric cable and cutting the electric cable to predetermined lengths, the stripping process for stripping an end of the electric cable cut to predetermined lengths, the terminal crimping process for crimping a terminal on a conductor in the end of the electric cable exposed by the stripping, the terminal inserting process for inserting the terminal crimped on the conductor in the end of the electric cable into a connector housing, the assembling process for assembling a plurality of electric cables mounted on the connector housing, and the like.
The respective manufacturing processes of the wiring harness have been automated due to rationalization such as decreases in manufacturing time and manufacturing cost of the wiring harness. Therefore, each electric cable processing station for performing measuring and cutting, stripping and terminal crimping operations is provided with a measuring and cutting apparatus 1, a stripping apparatus 2 and terminal crimping apparatuses 3, 4 and 5 for automatically performing the operations, as shown in FIG. 4.
In the measuring and cutting apparatus 1, the electric cable W must be guided in a U shape, measured and cut to predetermined lengths, and sent to the subsequent stripping apparatus 2 after clamping both ends of the electric cable W measured and cut. Accordingly, the measuring and cutting apparatus has been conventionally provided with an electric cable guiding device for guiding the electric cable W in a U shape.
This type of electric cable guiding device is disclosed in, for example, Japanese Patent Publication Nos. 5424/1989 and 5425/1989. In this electric cable guiding device, the front end of the electric cable W fed from a nozzle 13 is clamped by one clamp 14, as shown in FIG. 5. Thereafter, a reversely rotating member 15 is rotated through an angle of 180.degree. in a direction indicated by an arrow A1, to wind the electric cable around a wrapping board 16 and guide the same in a U shape. The electric cable W is drawn out while being measured by measuring rollers 11 and 12, and the electric cable W is clamped by the other clamp 17 at the time point where the electric cable W is fed by a predetermined length. Finally, the electric cable W is cut to predetermined lengths by a cutter 18.
However, the above described electric cable guiding device is so constructed as to clamp the front end of the electric cable W and rotate the reversely rotating member 15 to guide the electric cable W in a U shape. Accordingly, a rotating mechanism (not shown) for rotating the reversely rotating member 15 is required. Therefore, the electric cable guiding device is increased in size and becomes complicated. In addition, measuring and cutting time is increased by time for rotating the reversely rotating member 15.
In addition to the above described electric cable guiding device, various devices for guiding the electric cable in a U shape have been proposed. In guiding the electric cable in a U shape by such a device, however, an electric cable must be clamped/unclamped many times, so that its mechanism is complicated, and measuring and cutting time is long. Therefore, an electric cable guiding device which is small in size and is simple and in which measuring and cutting time is short has been desired.
The reason why the conventional electric cable guiding device is increased in size and becomes complicated is that the front end of the fed electric cable is first clamped and then, is guided in a U shape, so that a rotating mechanism is required and the electric cable must be clamped/unclamped many times. Therefore, the applicant of the instant application has considered a device for not first clamping the front end of an electric cable but first guiding the electric cable in a U shape and then, clamping the front end of the electric cable.